Progress spinner: buggy behavior in some terminal emulators

[woodruffw]

I've noticed this behavior in both iTerm and Alacritty on macOS: sometimes pip-audit's spinner will render once per line, rather than sticking to the same line.

Here's the buggy behavior on Alacritty:

and iTerm 2:

and here is is working correctly in Terminal.app:

I'm not really sure what's up with this: it only seems to happen when pip-audit is used with a requirements source rather than an environmental source, so it might be caused either by something we're printing differently for that source or by the slower steps in between actions. Needs debugging.

[di]

Looks like this happens when the line to be printed exceeds the width of the terminal:

https://asciinema.org/a/TIkTlhSX63EAFcbhmXf1hhU99

[woodruffw]

Thanks for catching that! This looks like the upstream issue: verigak/progress#40

Edit: And probably the same bug manifesting in pip: pypa/pip#6101